MELBOURNE, Australia — The head of U.S. Indo-Pacific Command says he has not had contact with his Chinese counterparts, despite a previous agreement between the U.S. defense secretary and the Chinese defense minister.

Speaking in Singapore on Thursday at an event hosted by the International Institute of Strategic Studies’ Asia branch, Adm. John Aquilino said he has not received a response to a standing request to speak with the commanders of the Chinese People’s Liberation Army’s Eastern and Southern Theater commands.

U.S. Defense Secretary Lloyd Austin and his Chinese counterpart, Wei Fenghe, in November agreed that it’s important for operational commanders to “have a conversation.”

“I have not yet received a response for a year-and-a-half to accept my request for a conversation,” he said. “I’ve not received a ‘no.’ I’ve not received a ‘wait, could we adjust?’ I’ve just received no answer.”

“We have continued to ask because I do think it is important. But it’s concerning to me I don’t have the ability to talk to someone, should there be a reason to talk,” he added.

Earlier this week, the commandant of the U.S. Marine Corps also expressed concerns about a lack of communication in the region following reports that an American intelligence drone crashed after colliding with a Russian fighter over the Black Sea.

“This is probably my biggest worry, both there and in the Pacific, is an aggressive Russia or China pilot or vessel captain or something gets too close, doesn’t realize where they are, causes a collision, and it’s 2 in the morning and we’re trying to unpack this as fast as we can. I really worry about that,” Gen. David Berger said at the National Press Club.

“Even more challenging because right now on our side, on the [People’s Republic of China], normally we would have communications with the [People’s Liberation Army Navy], their military. It doesn’t exist right now, they won’t communicate with us. So the normal, sort of many channels that you have to quickly diffuse something — they’re gone. They’re not gone, but they’re suspended right now,” he added. “So I worry, I do.”

However, the lines of communications remain strong with other countries within and outside of the region, Aquilino explained, adding that he has the ability to quickly contact foreign counterparts and vice versa. He said he hopes to have the same option with China, “but today it doesn’t exist, and it is not for the lack of trying.”

Aquilino also touched on lessons both the U.S. and China could learn from the ongoing conflict in Ukraine, which Russia invaded more than a year ago.

“No. 1: The ability to execute complex combined arms actions to achieve your objectives is difficult,” he said. “Synchronizing all those effects across all those domains, supporting it through logistics chains to deliver an effective fighting force that can sustain over time is hard.”

He also stressed that conflict “costs blood,” and that short wars “do not happen anymore, if it ever did.”

The cost of battle would also far exceed any projections, and the decision to enter one should not be taken lightly, he added.

Aquilino also rejected the assertion by China’s new foreign minister that war was “inevitable,” saying that it was important that regional countries, including China, know the U.S. is not pursuing conflict.

Qin Gang had warned at the closing of China’s 20th National Congress in Beijing earlier this month that war with the U.S. is inevitable unless the latter “changes course.”

Defense News’ Megan Eckstein and Marine Corps Times’ Irene Loewenson contributed to this report.

Mike Yeo is the Asia correspondent for Defense News.

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